Field of the Invention
The present disclosure relates to document scanners, particularly a flatbed scanner having laser lines projected onto a platen that define a scan area.
Background
Document scanners are commonly used to create digital representations of physical documents that can be digitally stored, transmitted, and/or edited. For example, many offices have been moving toward a “paperless” environment in which digital documents are preferred. Hard copies of paper documents are often scanned so that they can be transmitted via email or other means, stored on servers or hard disks, or edited with computer programs. Users working with photographs or other image-based documents can also desire to scan them in order to work with them digitally.
One type of document scanner is a flatbed scanner that has a platen, a window of glass or other transparent material, upon which documents can be placed. An image sensor in the flatbed scanner can be configured to move underneath the platen to scan documents resting on the platen. Flatbed scanners can be either standalone pieces of equipment, or be incorporated into larger devices. For example, a multifunctional printer (MFP) can include a printer, scanner, copier, fax machine, and/or other components in a single device.
Many flatbed scanners include a platen that is larger than the 8.5 by 11 inch dimensions of a standard US Letter-sized sheet of paper, such that the scanner can scan more than one page side by side on the platen, and/or scan documents in a variety of different sizes. However, many scanners are set by default to scan a specific section of the platen, such as an area with the dimensions of a single 8.5 by 11 inch US Letter-sized sheet of paper. Users who desire to scan a document of a different size may need to change the scan area from the scanner's default, either through setting on the scanner itself or through software on a computer or other connected device.
Although the scan area can be configurable, many users may not be sure of the exact dimensions of the document they want to scan, and thus be unsure of what dimensions to select for the scan area. In other cases, users may become frustrated when the edges of a scanned document are cut off because the wrong scan size was selected, or when users do not realize they should have changed the scan area from the default size.
Similarly, users who want to scan a non-rectangular document may not be sure which scan size to select in the scanner's settings to scan the full non-rectangular document. For example, a parent that wants to scan a child's artwork that has been cut out in the shape of a cartoon character's silhouette can be unsure of what size and shape scan area to select in order to fully scan the irregular shape of the artwork.
Even users that are scanning a standard sized document can be unclear on exactly where to place it on a larger platen. For example, the scan area is often set in a corner of the platen by default, but users may not be sure which corner is the correct one in which to place their document for scanning.
Some scanners solve these problems by performing a preliminary scan of the full platen as a preview, and displaying the results of the preliminary scan to a user as a preview image on a display, either on the scanner or on a computer or other connected device. The user can then click and drag a box around the preview image to select a specific scan area, or otherwise select a specific scan area they want within the larger area scanned during the preview scan. The scanner can then perform a full scan within the smaller area that was selected. However, this method can be slow and inefficient since it requires two scans and user interaction.
Some scanners attempt image recognition in order to find portions of the preview image that the user is likely to want to scan, and thereby automatically select a final scan area from a preview scan. However, such methods can still result in the incorrect scan area being selected. By way of a non-limiting example, portions of the platen covered by a piece of paper can have a different color or contrast than uncovered portions in the preliminary scan, and the scanner can set the scan area to an area that appears to have been covered by the paper in the preliminary scan. However, this automatically selected area may not be the actual area that a user wants to scan, or it may be sized to an area of high-contrast text while ignoring blank space on a page that a user still wants to scan. In this situations, user interaction is still required to confirm or modify the dimensions of the scan area before a final scan is performed, and two scans are still required.
While some documents scanners use a preliminary scan as described above to confirm the desired scan area, scanning documents on a MFP is often done directly at the MFP alone without the use of a connected computer or other device that can display the results of a preview scan. Instead, the specific dimensions of the desired scan area are typically selected at the MFP prior to the scan, and the resulting digital representation is immediately stored on a server or other memory device for later use, or transmitted directly to another device or location. In these cases, no opportunity exists for a user to review the results of a preliminary scan before a final scan takes place.
Another solution to the problem of where to place documents on the platen, and what scan area to select, has been to mark various scan areas directly on the platen with lines. For example, translucent lines defining the boundaries of scan areas can be marked on the platen in a color that will be ignored by the image sensor, so that the lines appear invisible in the final scan. However, such lines can become discolored over time, such that they are no longer invisible to the image sensor and lines appear in the scanned image.
What is needed is a document scanner with laser line indicators projected onto the platen that mark the boundaries of the current scan area. The laser line indicators should also be movable to allow user to visibly change the dimensions of the scan area prior to scanning.